ISSN 2996-8215
International Journal of Cardiology | Vol. 13, No. 6, June 2022 | pp. 41–48
DOI: 10.46882/2022/IJC/000159
Review Article
Diagnostic Advancements and Risk Stratification Matrices via Multi-Parametric CMR Mapping in Non-Ischemic Cardiomyopathies
Sarah L. Jenkins¹, David M. Ross²
¹Department of Cardiovascular Imaging, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
²Division of Cardiology, Alfred Hospital, Monash University, Melbourne, Victoria, Australia
Abstract:
Non-ischemic cardiomyopathies (NICMs) exhibit diverse etiopathology, requiring advanced tissue tracking to optimize clinical management. Traditional late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) imaging pathways reliably identify focal replacement scars but remain insensitive to early microscopic diffuse interstitial expandings. This comprehensive review synthesizes recent registry data evaluating quantitative multi-parametric CMR mapping sequences—specifically native T1 mapping, T2 mapping, and calculated extracellular volume (ECV) fractions—across major adult NICM phenotypes. A structured review compiled findings from 38 clinical databases representing 4,120 individuals. Parametric T2 mapping sequences demonstrate excellent specificity for identifying active localized inflammation in acute myocarditis, providing a pooled diagnostic accuracy of 89.5% against tissue biopsies. Concurrently, native T1 and ECV metrics quantify diffuse interstitial matrix expansion in dilated and hypertrophic configurations before macroscopic scars develop. Aggregated data indicate that an elevated baseline ECV fraction greater than or equal to 32% provides an adjusted hazard ratio of 2.12 (95% CI: 1.41–3.46, p < 0.01) for predicting progressive heart failure hospitalization. Multi-parametric quantitative CMR mapping provides non-invasive mechanical tracking that maps diffuse tissue variations, enhancing diagnostic specificity and risk stratification across non-ischemic cardiomyopathies.
Keywords: Cardiac magnetic resonance, Parametric mapping, Extracellular volume fraction, Non-ischemic cardiomyopathy, Myofibrosis, Prognosis
Received: March 11, 2022; Revised: April 25, 2022; Accepted: May 12, 2022; Published: June 19, 2022